CocoaPods is an Objective-C library package manager. It tries to take away all hard work of maintaining your dependencies, but in a lean and flexible way. Its goal is to create a more centralized overview of open-source libraries and unify the way in which we deal with them.
CocoaPods will calculate the right set of versions of all of your project's dependencies, install them, and set them up to be build as part of a dependency static library, which your project links against.